like why?
everything must die eventually lie out with the old and in with the new
why waste resources transporting stone from somewhere else when its right tehre and not being used for anything
old buildings get torn down all the time

I don't see why. You keep this shit around for two reasons: to discover culture; to make money. If tourists aren't going to it because it's a lifeless block, and the government gives you the permission because they believe they've discovered all the culture of the place on the outside, why not take it apart and see how it was built and then turn it into a road?

But it would be more like my great great great great great great great great great great great great grandparents graves that I never even knew I had. Also it is there country and their monuments, why should anyone but the people that live there have a right to say anything about it?

Oh thats fine then, its just spitting on the graves of their ancestors. A people that fought its god damn hardest to resist conquest, and all that remains of them are these monuments, things we don't build anymore, and even if we try to replicate it, it won't be the same.

But who the fuck cares about that, right? Its only an important part of South American history and culture. Fuck it, why not destroy the Colosseum at Rome too? Every Greek temple, the Pyramids in Egypt, Stonehenge, every monument of past civilizations that show the history and glory of our species.